This invention relates to slot machines and, in particular, to a variable award multiplier feature for a slot machine.
Slot machines employing mechanical reels or video reels are the most popular gaming machines in a casino. Details of such conventional slot machines are found in U.S. Pat. No. 4,095,795 to Saxton et al.; U.S. Pat. No. 4,448,419 to Telnaes; and U.S. Pat. No. 4,573,681 to Okada, all incorporated herein by reference.
Although prior art slot machines are attractive, there is a constant need to increase revenue generated by the machines. Such an increase is typically met by enhancing the machines"" appeal to the players. Accordingly, what is needed is a slot machine with more player appeal.
An improvement on a slot machine is described herein which allows a player to participate in an additional game of chance, namely a variable bonus multiplier (VBM) determination, to obtain an award multiplication factor that multiplies the award for a previous play. The invention may be implemented by relatively minor changes in a prior art slot machine""s firmware/software program and pay-table ROM and the addition of a multiplier display.
In the preferred embodiment, the multiplier feature is initiated by the display of a special symbol in a winning combination of symbols. The multiplier factor is generated using a weighted probability routine that assigns unequal probabilities to the possible multiplication factors. Thus, the lower multiplication factors will have a higher probability of being selected than the higher multiplication factors. This results in greater player appeal without incurring a significantly increased payout/pay-in ratio.